Control of electrically-operated switches.



H. E. WHITE 6: E. R. GARIGHOFP. CONTROLOP BLEGTRIGALLY OPERATED SWITGHES. APPLIUATION FILED 313.27, 1909.

969,585. I Patented Sept. 6,1910.

, Hanazz: 3. mars.

A TT'X UNITED- STATES PATENT OFFICE.

HAROLD E. WHITE AND EUGENE R. GARICHOFF, OF- SCHENECTADY, NEW YORK, AS

SIGNORS TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

CONTROL OF ELECTRICALLY-OPERATED SWITCHES.

Patented Sept. 6, lots,

Application filed February 27, 1909. Serial No. 480,483.

To all whom it may concern:

Be it known that we, HAROLD E. WHITE and EUGENE R. Clinionorr, citizens of the United States, residing at Schenectady, in the county of Schenectady and State of New York, have invented certain new and useful Improvements in Control of Electrically- Operated Switches, of which the following A is uv specification.

Our invention relates to the operation and control of electrically-controlled switches and particularly to the o oration successively in s certain order or o plurality of such switches. It is especially useful in connection with systems of motor control in which at plurality of electrically-controlled switches or contsctors are errenged to operate in succession to increase stepby-step the voltage applied to the motor. Arrangements of this kind are employed in starters.

for electric motors and have been so arranged that, by closing a single mesterswitch, contectors are caused to operate sutomaticslly in succession to cut out section by section resistance interposed in the motor circuit on starting, or, in some other way, to

increase step-by-step the voltage applied to the motor. Similar arrangements have also been used in systems of motor control in which the master-switch has 2. plurnlity of on posit-ions end serves-to regulate the rate ofsuccessive operation of the cont'sctors de nd upon the currentin the motor circ111t,jthot'1s, that the operation of 21 succeeding contsctor'be prevented it" the closing of preceding contector has resulted in producing current in the motor circuit in excessoii o cert-sin safe value. Vorious arrangements have been used for giving this so-called end current'limit to the action of s series of switches usedtor the above descrihcd purposes, one or the best known'heing' the system inwhich n notching relay? is arranged to interrupt the actuating circuit for the series of switches after each switch has operated and to maintain said circuit interrupted as long as the current in the motor circuits exceeds a. certain' value.

- It is a general object of our invention to provide a. new and improved system of control for a plurality of electrically controlled switches or contoctors intended for operation in succession under the control of the varying conditions in the power circuit in which said contactors efiect certain connections.

()ur invention comprises an arrangement in which a. plurality of contsctors, intended for operation in succession, are each controlled by an auxiliary switch which coo crstes with .a preceding contector end which is positively held open while ssid contactor is open, an electromsgnet being provided for each auxiliary switch which is energized from the power circuit to be controlled and which controls the closing of said auxiliary switch after its cooperating cont-actor has closedl in the particular iernhcdiment our invention hereinafter described, we use, in. connection with e plurality of contcctors intended for operation in succession to effect certain connections in at power circuit, sunilisry switches each of which cooperates with a contuctor and serves to control the succeeding cont-stator, n connection being provided between each contsctor and its cooperating auxiliary switch, whereby when the former is open the letter is positively held open end when the former is closed the latter is permitted to close, magnets, all of which are energized upon the completion of the power circuit being arranged to'control the closing of each auxiliary switch,-end the connections being such that each contoctor in closing hesi es efiecting the desired connection in the power circuit also shunts the magnet of the auxiliary switch which controls said contector.

In the drawing we hove'shown diagramfmstically our invention as applied. to simple system of control for it direct current .niotor, but this is merely illustrative end,

he will be obvious to those skilled this art, It rnefiy equally well he applied to other forms of dynamo-electric machinery and to other types of control; or, in feet, employed in any connection where it is desired to regulate the conditions in a power circuit by means of a plurality of switches operating in succession.

Referring tothe'd-rawing, a source of current is indicated at 'l, with which the power and control circuits of the system are connected through a switch S. The armature A starting or control resistance is shown as made up of sections R R R and R" which may be short-circuited by suitable electrically-operated switches or contactors l, 2, 3 and a, respectively. A master-switch K is shown developed, in the usual conventional manner, and as of type in which a drum,.provided with suitable segments, cooperates in both directions from 0E position with a-set or fingers a, b, c, d, c, f, g

, andh and serves to regulate the operation of the contactors for both directions of rotation of the motor. Contactors L and L are provided with interlocking switches Z and Z of any well-known- :form, shown in the usual conventional way, which are closed when the co-ntactors L and L are open and are opened by the closing of the latter. Switches U, L, 1, 2 and 3 are each prorided with an attachment which consists of an auxiliary or interlocking switch 10, to the movable element of which is secured a core 11 which is arranged for movement in a magnetic field produced by a conductor or coil arranged in cooperative relation to the core and carrying motor current, The movablemember of each auxiliary switch 10 and its codperating core. 11 is mechanically connected-in any suitable manner to the movable member of its corresponding contactors L L 1, 2 or 3 and is held in its raised position, as shown in the diagram, when its corresponding contactor is open.

In the arrangement d1agrammatically illustrated, the core 11 has extending upwardly from it a rod 12 which at its upper end is bent into a hook 13,- the downwardly extending end of which rests upon a heel vlet of the movable contact member of the contactors U, L l, 2 and 3. With a construction of this kind when any one of said contactors is open the core 11 of its auxiliary switch is held in its raised position and this switch is therefore open; but when a contactor closes the heel l4'moves away from the end of the hook 13 and the switch l0 1s free to close unless prevented ashorelnafter explained. The magnetic field structures and the magnetizin coils of the auxiliary switches 10 are so esigned that 'movement of the core.

eeassa said switches will be held open, when released by the closing of their corresponding contactors, if the current in a conductor or coil which coo crates with their cores 11 is in excess 0 a -certain value, in other words, if the current in the motor at that time exceeds a certain predetermined safe value. When, however, a core 11 has dropped, no increase in motor current thereafter will cause it to pull up.

The particular design of auxiliary switch mechanism necessary to the carrying out of the'functi'ons just mentioned will be at once apparent to those skilled in this art, it being well known that the operation of a core ot magnetic material in the field of an electromagnet can be regulated by properly arranging the number of ampere turns in the magnet coil and the field structure of the magnet, particularly the air gap in the magnetic circuit which varies with the The characteristics and the design of electromagnetioally-operated devices are now so well understood that the diagrammatic illustration of our device and the statement of its functions is suliicient to enable any one skilled in the art to build the same.

As will be evident from the followin description of the mode of operation or the system, the auxiliary switches 10 which c0- operate with the contactors L and lf-control the energization of the actuating circuits for the resistance controlling contactors 1, 2, 3 and a; and the auxiliary switches 10 which cooperate with the 'ccntactors l, 2 and 3 are located respectively, in the control circuits to the actuatin tactors 2, 3 and 4. T e arrangement of motor and control circuits will be an arent from the dia ram and from the folfdwing description or the mode of operation of the system.

The switch S being closed and the masterswitch K being thrown to its first forward position, a circuit is completed from the side of the source, through the wire 15 through the two upper fingers a and b and cooperating segments on the forward side of the master-switch tothe wire 16, thence to the actuating coils of the contactors L and L in series, through the, auxiliary switch Z on the .contactor L to the side of the source. The contactors L and L will, therefore, close and a circuit will be completed from the positive side of the source through the field F of the motor, contactor L armature A, contactor L through all of the resistance R R R and R to the side of the source. It is to be observed that this circuit passes through the conductors or coils which produce the magnetic fields operating ,upon the cores ll of the attachments to contactors L L 1 2 and 3 and that, even though released by the coils of the con-' closing of their corres onding contactors, these cores will not 3111 and cause the switches, 10 to close if the motor current exceeds a certain value. As long as the master-switch K remains in its first on position no further changes in the motor circuit take place and the motor will be connected to the source with all the resistance in circuit. If the master-switch K is moved to its second forward position, the two lower fingers g and h thereof en e with their cooperating segments, and il the current inthe motorcircuit'has fallen to such a value that the auxiliary. switch 10 cotiperatin with the contactor L has closed, a circuit is completed from. the wire 16, through the switch 10 on the contactor L, through wire 17 through the two lower fingers'g and h and their segments on the master-switch to the wire 18, and thence throu h the actuating coil of the cont-actor 1 to t e side of'the line through the conductor which cooperates with the cores 11 of the attachments to the contactors 1, 2 and 3. The" cont-actor 1 will, therefore, close and will short circuit the section of resistance R As long as the master-switch K remains in its second position no further operation of the contactors will occur. If, however, the master-switch is thrown to its third forward position,- the finger 1 will engage with its coiiperating segment and the wire 19, leading to the auxiliary switch 10 of the contactor 1, will be energized as was wire 18 and, if the current in the motor circuit has dropped below a certain predetermined value and the auxiliary switch 10 cooperating with contact/or 1 has therefore closed, a circuit will be completed through the actuating coil of the cont-actor 2 which will close, short-circuiting the section of resistance R.

From the foregoing it will be clear that the motor may be connected to the source and the resistance cut out section-by-section by movin the master-switch K through its various on positions, and that during this operationil the motor current exceeds a certain value the successive operation of the resistance controlling contactors 1, 2, 3 and,

4 will be retarded.

It is, of course obvious that, if desired, the master switch K may be thrown at once to its fifth or full on position whereupon the operation of the contactors will take place automatically under the same limitations in the rate of closing as in the mode of operation alcove referred to.

We have not deemed it necessary toillustrate in this application any particularly mechanical construction of contactor and auxiliary switch attachment therefor, since it will he obvious to those skilledin the art that our invention may he embodied in many different constructions. The contactors may he of the same general nature as that shown in the resent application.

W hile we have shown our invention as incorporated in a. system of motor control having switches or contactors which are electromagnetically operated, we realize that it may equally well be used in connection with systems in which the switches are operated pneumatically. It is, therefore, our intentention to cover such systems in this application and wherever we have used the expressions electrically cont-rolled switch or contactor we mean to include both those which are operated electromagnetically and those which are operated electro-pncuniatically, these two systems bein now well thermore, while we have shown our invention as embodied in a system in which the magnet coils of the auxiliary switch attachments are traversed by the entire motor or power current, we do not wish to he understood as limiting it to this arrangement, since, of course, these magnetizing coils may be energized from the motor or power cir= cuit in many different ways as is well known to'those skilled in the art.

It will be obvious to those skilled in this art that our invention be embodied in a great variety of forms, and it is our in tention to cover in the lollowin claims all such embodin ents as come within the scope of our invention.

What we claim new and desire to secure by Letters Patent oi the United States, is,-

1. Incoinbination with a power circuit, a plurality of contactors intended for open ation in succession to effect certain connections in said power circuit, actuating magnets i or said contac'tors, auxiliary switches coiiperat-ing with certain of said contactors, each arranged to control the operation of a succeeding contactor, means for positively holding each auxiliary switch open while coiiperating contac'tor is open, and electrical means independent ofsaid actuatin magnets ;lor controlling theiclosing of said an iliary switches.

2. in combination with a power circuit a plurality of contactors intended for opera ation in succession to effect certain connections in said newer circuit, actuating nets for said contactors, auxiliar switches coiiperating with certain of said .contactors, each arranged to control the operation of a succeeding cont-actor, means for holding 'each auxiliary switch open while its cotiperplurality of contactors intended for oper-- ation in succession to efiect certain connections in said power circuit, actuating magnets for said contactors, auxiliary switches cooperating with certain of said contactors, each arranged to control the operation of a succeeding contactor, means for holding each auxiliary switch open while its cooperating contactor is open, a magnet cooperating with each auxiliary switch and energized from the power circuit for controlling the closing of said auxiliary switch, and connections whereby each of said contactors in closing shunts the magnet of its controlling auxiliary switch. i

4-. In combination with a power circuit, a plurality of cont-actors intended for operation in succession to erlect certain connections in said power circuit, auxiliary switches cooperating with certain of said contactors, each arranged to control the operation of a succeeding contactor, a connection between each of said contactors and its auxiliary switch whereby when the former is open the latter is positively held open and when the former is closed the latter is permitted to close, a magnet cooperating with each auxiliary switch and energized from the power circuit for controlling the closing of said auxiliary switch, and connections whereby each of said contactors in closing shunts the magnet of its controlling auxiliar switch.

5. In com ination with a power circuit, a plurality of contactors intended for operation in succession to efiect certain connections in said power circuit, actuating magnets -for said contactors, auxiliary switches cooperating with certain of said contactors each arranged to control the operation of a succeedin cont-actor, means for holding each auxlliary sw1tch open while its cooperating contactor is open, a, magnet cooperating with each auxiliary switch and energized from the ower circuit for controlling the closing oit said auxiliary switch, and connections whereby each contactor in closing both 'efiects the desired connection in the power circuit and shunts the electromagnet cooperatin with the auxiliary switch which contro s the control circuit for that contactor.

6. In combination with a ower circuit, a plurality of switches inten ed for operation in succession to effect certain connections in said power circuit, auxiliary switches cooperating with certain of sad first mentioned switches, each arranged to control sconce closed the latter is-permitted to close, and

inezmsener'gized from-the ower circuit for controlling the closing 0 said aux1l1ary switches.

7. In combination with-a power circuit, a plurality of electrically controlled switches intended for operation in successionto efiect certain connections in said power circuit,

control circuits for said switches, auxiliary switches cooperating with certain of said electrically controlled switches and each arranged to control the control circuit of a succeeding electrically controlled switch, a connection between each electrically controlled switch and its auxiliary "switch whereby when the former is open the latter is positively held open and when the former is closed the latter is permitted to close, and means responsive to current in the power circuit for controlling the closing or said auxiliary switches.

8. In combination with a power circuit, a plurality of switches intended for operation in succession to effect certain connections in said power circuit, auxiliary switches cooperating with certain of said first mentioned switches, each arranged to control the operation of a succeeding switch, a mechanical connection between each or" said first mentioned switches and its auxiliary switch whereby when the former is 0 en the latter is positively held open and w en the'it'ormer is closed the latter is ermitted the operation of a succeeding switch, a con to close, and means energized rom the power circuit for controlling the closing 0 said auxiliary switches.

9. In combination with a power circuit, a plurality of electrically controlled switches intended for operation in succession to efiect certain connections in said power circuit, control circuits for said switches, auxiliary switches cooperating with certain of said to close, and means responsive to current in the power circuit for controlllng the closmg' of said auxiliary switches. y

10. In combination with a power circuit, a lurality of electrically controlled switches lntended for operation in succession to efiect certain connections in said power circuit, control circuits for said switches, auxiliary switches cooperating with certain of said electrically controlled switches and each ar- 1 close,

switch whereby when the former is open the latter is positively held open and when the former is closed the latter is permitted to and electromagnetically operated means energized from the power circuit for controlling the closing of said auxiliary switches.

11. In combination with a power circuit, a plurality of electrically controlled switches intended for operation in succession to effect certain connections in said power circuit, control. circuits for said switches, auxiliary switches cooperatingwith certain of said electrically controlled switches and each arranged to control the control circuit of a succeeding electrically controlled switch, a mechanical connection between each electrically controlled switch and its auxiliary switch whereby when the former is open the latter is positively held open and when the former is closed the latter is permitted to close, and electro-magnets energized from the power circuit for controlling the closing of said auxiliary switches.

12. In combination with a power circuit, a plurality of contactors intended for operation in succession to elfect certain connectionsin said power circuit, control circuits for said contactors, auxiliary switches each cooperating with a contactor and arranged 'to control the control circuit of a succeeding contactor, a mechanical connection between each contact-or and its auxiliary switch whereby when the former is open the latter is positively held open and when the former is closed the latter is permitted to close, and an electromagnet the energization of which depends upon the current in the power circult arranged to prevent the closing of said auxiliary switch if the current in the power.

circuit exceeds a certain value.

13. In combination with a power circuit, a plurality of contactors intended. for operation in succession to effect certain connec- 'tions in said power circuit, control circuits for said contactors, auxiliary switches having fixed and movable members cooperatingwith certain of said contactors and each 'arranged to control the control circuit of a succeeding contactor, a mechanical connection between each contactor and its auxiliary switch whereby when the former is open the latter is positively held open and'when the former is closed the latter is permitted to close, an armature of magnetic material connected to themovable member of said auxiliary switch, and a coil energized from sald ower circuit and arrangedto magnetically influence said armature and thereby control the closing of the auxiliary switch. I

14. In combination with a power circuit, a plurality of cont actors intended for operation in succession to effect certain connections in said power circuit, control circuits for said contactors, auxiliary switches having fixed and movable members cooperating with certain of said contactors and each arranged to control the control circuit of a succeeding contactor, a mechanical connection between each contactor and its auxiliary switch whereby when the former is open the latter is positively held open and when the former is closed the latter is permitted to close, an armature of magnetic material connected to the movable member of said auxiliary switch, and a coil energized from said power circuit and arranged to magnetically influence said armature and maintain said auxiliary switch open if the current in the power circuit exceeds a certain value.

15. In combination, a contactor, a relay, and a mechanical connection between said contactor and said relay whereby when said contactor is open the contacts of the relay are held open and when said contactor is closed said relay is operatively independent.

16. In combination, a contactor havin a movable member, a relay having a mova le member, and a mechanical connection between the movable member of the contactor and the movable member of the relay whereby when the former is in one position the latter is held in one position and when the former is in its other position said mechanical connection is ineffective.

' 17. In combination, a contactor having a pivoted member, a: relay having a longitudinally movable member, and a mechanical connection between said pivoted member and said longitudinally movable member whereby when the former is in one position the latter is positively held in one osition and when the former is in its ot er position the latter is movable independently of the former.

18. The combination with a contactor having a fixed contact member, a movable contact member, and an actuating coil for moving said movable contact member into engagement with said fixed contact member, of an auxiliary switch attachment comprising a fixed contact member, a movable con- I ing a fixed contact member, a movable contact member, an actuating coil for moving said movable contact member into engagement with said fixed contact member, of an auxiliary switch attachment comprising a fixed contact member, a movable contact member, a mechanical connection between the movable contact member of said contactor and the movable contact member of said auxiliary switch attachment whereby when said contactor is open the contacts of said auxiliary switch attachment are held open and when said contactor is closed the contacts of said auxiliary switch attachment are permitted to close, and a magnet coil for controlling the closing of the contacts of the auxiliary switch attachment.

20. The combination with a contactor having a fixed contact member, a movable contact member, and an actuating coil for movmg said movable"contact member into engagement with said fixed contact member, of

an auxiliary switch attachment comprising ceases a fixed contact member, a movable contact member, a mechanical connection between the movable contact member of saidcontactor and the movable contact member of said auxiliary switch attachment whereby when said contactor is open the contacts of:

'with the movable contact member of said auxiliary switch attachment.

In] witness whereof, we have hereunto set our hands this 26th day of February, 1909.

Witnesses:

BENJAMIN B. HULL, HELEN Garcia). 

